Reproducer for talking machines



E. M. LOW.

REPRODUCER FOR TALKING MACHINES.

APPLICATION FILED gnAY12, 1919.

1,424,83 PatentdAug. s, 1922.

7 62 0 F'- a H 2 INVENTOR .euan STAKE caries.

nvnnnr'r in Low, or nnoonnvn, new YORK.

REPRODUCER FOR TALKING MACHINES.

Specification of Letters Patent.

1,424,838. Patented ne e, 1922."

Application filed. May 12, 1919. Serial No. 296,622.

- chines in which sounds are reproduced from sounds previously recorded on a record.

. The. object of my invention is toprovide aninstrument which will reproduce faithfully, sounds as they are recorded, and-prevent the introduction of elements into the reproduced sounds that are not in the record or othersource of reproduction,

I attain this object by the device illustrated in the accompanying drawing in Figural is a side view. Figure. 2'is an edge view looking in direction of arrow 3 Fig. 1, shown sectioned online-xw,Fig.1;- 1

Figure 3 is an edgeview looking in directionoi arrow 2., Fig. 1 the needle holder being removed, the better to showother parts;- r

Figure 4cis a view of the bridge f. Fig. 5 is anelevation of the bracket 6.

Referring to the drawing in which similar reference characters refer to the same parts lthroughoutthe several views;

a, is .a sound box having the diaphragm a held between rings a and a of rubber, paper or similar materials and issecuredby the metal ring a in a manner well known in the art;

- The sound box chat; the hub a gae shown in Fig. 2, the bore a being shown in dotted lines, for 'attachmentto the tone arm of a talkingmachine in the usual manner.

b, is alever having at its end 6 the needle holder 6 and the needle 19*. v 0, is a tensionbar which rests on the lever 79 at its ends 0 and 0 the, tension Ibar being cut away between the ends. 0 and-c to re duce thecontact surface and give it a yield ing tension under pressure. 1

cZ, is a bracket secured to the sound box a, serving as a support for the fulcrum (F; the cap (Z3, and the screws 6%, and 03 these parts together with the tension bar 0, serve as asupport and a confining means for thelever b, nearits end 6 t e, Iis a second bracket similar to the bracket d, the-bracket 6 being secured to the sound box a and 'servlng as an equalin ing support for the lever b, at its-end b The bracket c, has the cap 0 and the.

screws 6 and c andthe equalizing blocks 6 and e. c The bracket 6 is shown in Fig. 2 ashaving one side broken away to more clearly show the blocks 6?, and e. i

' ',.is a bridge contacting with the lever Z2,

at ffland withthe diaphragm a at. f and the bridge being cut awaybetween f and f, to reduce the amount of contact surface with the diaphragm c The bridge at F and f contacts withthe dia' phragm' at points of greatest vibratilityyor about midway between the center and the periphery of the diaphragm; the radial distancei'rom the center when the diaphragm has the greatest vibratility being between four and five tenths of the radius. The lever b isa rigid bar, that is, it is not flexible or springy and is preferably of glass, as glass-is elastic and returns quickly and positively to its normal state, after. be.- ing subjected to an impact or disturbance of its structure. v

Other materials may bev used such as ivory, hardened steel or hard wood but as far as I have been able to determine, glass meets the requirements better than any other material. i

vThe. lever 22-, when used in a reproducer for a talking machine for the reproduction of sounduirom .a record, is. provided! at its end 6?, with a needle holder b iand a needle 6 similar to ones used in the art. The lever Z), is supported on the fulcrum d resting on the bracket (Z, attached to the soundbox a. 7 l

The fulcrum d is preferably of hard wood or any hard now-vibratile substance; or a pivot may be used instead of the ful crum cl, shown inthe-drawing. J The lever b, restscn thebridge f, and

the bridge f, rests onthe diaphragm a the c bridge f, is: preferably of hardwood and may be at the centeroi' the diaphragm. 60?, as shown but this is not essential as it may be located at some distance from the center and produce practically the same results, except the bridge 7 is .made shorter and has a singlecontact point with the diaphragm a when there is an advantage inlocating it off center, which will produce more overtones.

The tension bar 0, is preferably of hard Wood and rests at its ends, and 0 on the lever- Z), the end 0 being between the ful- V crum (Z and the end 19 ofthe lever b, and

crum oZ and a lesser contact of the lever b,

with the bridge 7, to force the bridge 7, on

the diaphragm a suflicient to give the diaphragm a a slight tension.

The'lever b, at its end 6 is held between the equalizing-blocks 6 and e, the equalizing blocks 6 beingforced on to the lever b and the lever b on to'the equalizing block 6, and the equalizing block 6, on to the bracket 6, by the cap 6 and the screws 6 I and 6 I, terials may be used, as soft wood, cork or screws 6 and c The equalizing blocks'e and eflare made preferably of wood and rubber, the wood being in contact with the lever 6, other maleather. i I

The equalizing blocks and their co-acting parts are for the purpose of equalizing the tension on the diaphragm a if there is too great a tension on the diaphragm a the block a, would be-made thicker and if the tension on the diaphragm a is not great -enough the block 0", would be made thinner,

the'cap e being'adjusted according to the thickness of the block e,

by means of the The ob'ect of this equalizing device is to correct any deviation from the correct tension of the diaphragm produced by the lever 6, through the tension bar a, the cap 03 and screws (P and (Z and to confine thelever b, at its end '6 between slightly yielding clamps by which rebounding of the lever b and over vibration of the diaphragm a is prevented. I

I have specified in each instance the kind of material of which the several parts are preferably composed, Ido not limitmyself to anyparticular material, as the tension bar-'0, is made preferably of wood for no duction of 'otherrea'son than toavoid the production of unrhythmical vibrations by the contact of highly vibrative materials. p

I It is obvious that'the tensionbar 0, might be made of metal if its contacts'with other vibrative parts were insulated by the introthin pieces of non-vibrative material.

p Having thus described my invention what I claim and desire to secure by Letters Patent is: r

'1. A sound box having a diaphragm, a lever adapted toyreceive vibrations, a bridge tions, a connection between the lever and the sound emitting member, a support on the sound box I for the said lever, a confining means for reta ning the lever on the support and on theconnection and the connection on p the diaphragm; the sald confining means 111- eluding a tension bar having a plurality of contacts with the lever, the said contacts be ing so disposed as to cause the lever under the actions of the compressing means to be forced into a firm contact with the support and into a less firm contact with the connection; a second support on the sound box and a second confining means for retainingthe lever on the said second support and equalizing means to equalize the tension onthediaphragm produced by the connection, the

lever, and the confining means.

3. A sound box having a d-'aphragm,"a lever adapted to receive vibrations,the said lever being fulcrumed on the sound box, the fulcrum engaging oneside of the lever and a tension bar engaging the other side of the lever, the tension bar having contacts at its ends, the said contacts straddlingthe said fulcrum, a bridge connecting thelever and the diaphragm and means for applying pressure to the tension bar to force the lever against the bridge and the bridge against the diaphragm. u

4. A sound box having a diaphragm, a lever provided with a needle and a bridge between the lever and the diaphragm, the

lever having an incompressible support on one side of the sound box and extending across to and having a second support on the opposite side of the sound box, a confining means for retaining the lever on the said incompressible support and a second confining means for retaining the lever .on-the said sec- 0nd support, the said second support having an equalizing means to equalize thetens'ion on the diaphragm produced by the lever and 1 the confining means acting on thebridge and on the diaphragm.

5. A sound box, having a diaphragm, a lever having a fulcrum on one side of the sound box, abridge between the lever and the diaphragm, a tension bar and compressing means for the purpose of forcing the lever onto the fulcrum and onto the bridge, and on the opposite side of the sound box an equalizing means to equalize the tension of v the diaphragm produced bythe action of the tension bar having a plurality. of contacts with thelever, one of the contacts being at a greater distance from the said connection than the distance of the support from the 15 said connection.

7. A sound box having a sound emitting member, a lever adapted to receive vibrations, a support on the sound box for the said lever, a connection between the lever and the, sound emitting member; a tension bar having a plurality of contacts with the lever and means for forcing the tension bar on to the lever and the lever on to the support and on to the connection, the contacts of the tension bar with the lever being disposed in such manner as to cause the lever to be forced into a firm contact with the support and into a less firm contact with the said connection to give a tension to the diaphragm.

In testimony whereof I affix my signature.

EVERETT M. LOW. 

